The present invention relates to a drifting training assistance system for learning the drilling technique in a motor vehicle.
One necessary part of a driver training course is drifting (e.g., in a circle), where the rear wheels are intentionally accelerated so intensely that the rear of the vehicle moves round and a great side slip angle is generated. This has to be learned without any support from an assistance system.
During drifting, a driver tries to cause his vehicle to oversteer, whilst maintaining control and keeping the same driving speed. During such driving maneuvers, the rear wheels have a larger slip angle than the front wheels.
During drifting, mostly light vehicles having rear-wheel drive with high engine power and torque are used. A rear-wheel drive offers the advantage of controlling the drill angle in a targeted manner via the spinning of the rear wheels, i.e. via a provoked oversteering, through sheer excess in engine power. Vehicles with a front-wheel drive are less suitable for drilling because they tend to understeer rather than oversteer during acceleration. In the case of a vehicle with front-wheel drive, however, oversteering can be generated b applying the handbrake. However, this is referred to as “slide” rather than “drift”. These “slides”, too are addressed by the present invention.
A further technique consists in causing the vehicle to carry out a reciprocating movement. In the course of this, the driver tries to drive in small serpentine lines, so that the rear of the vehicle breaks out in the case of a sudden and strong steering maneuver.
A further technique consists in briefly placing the rear axis of the vehicle on a grass surface next to the road. In the course of this, swinging motions of the vehicle build up in such a way that the rear slides over the surface next to the asphalt and thus loses its grip. As soon as the input drill angle has been reached, the vehicle is moved back onto the asphalt.
The handbrake (optionally electronic) itself can not only be used for initiating drifting, but can also be used for markedly prolonging a drifting process, by causing an instable driving condition, whilst the vehicle already tends to establish grip on the rear axis. A further possibility of using the handbrake is the reduction of excess speed between bend combinations. If, for example, a driver drifts around a bend in fourth gear and a bend requiring a drift in second gear follows, it makes sense to abruptly increase the drift angle prior to driving into the slower bend by means of the handbrake and thus to reduce the speed whilst sliding into the bend.
Taking bends (curves) using the drifting technique requires great skill, but in addition affords the security of controlling the vehicle even in critical situations. Corresponding drifting skills can be obtained in special courses that are offered.
However, it is in particular the simultaneous steering and accelerating that causes the greatest problems to many course participants, even after many training sessions, so that oftentimes a satisfying learning outcome has not been achieved at the end of the course.
It is therefore the object of the present invention to provide a remedy for this.
Accordingly, to the invention, this and other objects are achieved in a drifting training assistance system for a motor vehicle for learning the drifting technique (e.g. in a circle) required in high-performance driving training by having both the steering activity and the gas pedal movement, or the combined action thereof, taken over and/or supported by at least one drifting assistance system. Alternatively, also handling instructions of an optical and/or acoustic type may be provided to the driver.
As a result of the measures according to the invention, it becomes possible for the course participant to obtain to demonstration from the assistance system of the steering movements required for drifting directly from behind the steering wheel. Subsequently, they can learn the steering and accelerating independently from each other and can in this way obtain an at least satisfactory learning success by the end of the course.
According to an advantageous development, the drifting assistance system continues the course curvature of a vehicle-fixed reference point that is available during the activation thereof and is determined from the yaw rate, the lateral acceleration or from UPS sensors, by way of automatic steering movements.
The automatic steering movements are advantageously continued even if the rear of the motor vehicle breaks out as a result of an acceleration that is administered by the driver or by the drifting assistance system itself.
In order to adapt the course of the vehicle to the local conditions of the training ground, it is provided according to a preferred embodiment that the controlled course curvature can be adapted via a controller.
Alternatively, also the manual torque applied b the driver may be measured, on the basis of which the required course curvature (e.g. by up-integration of the signed manual torque) is corrected. The driver then has the possibility of following the automatic steering movements with his hands and to push “against the controller” in a dosed manner only in the case of as desired course correction corresponding to the required direction.
According to an advantageous development, the drifting assistance system determines the side slip angle of the center of gravity of the vehicle that is present during the activation thereof and is determined from the steering angle, the yaw rate, the lateral acceleration or reference sensors such as GPS, and controls the estimated side slip angle to a required value adjustable by the driver by way of acceleration or deceleration.
An advantageous development relates, rather than to active driver interventions, to the acoustic or optic representation of the controller actuating variables. If the driver follows these handling instructions (e.g. the required and the actual position of the steering wheel angle in the head-up display, the difference between the required and the actual gas angle using a pitched tone), the same desired system behavior is represented as if the controller directly accessed the steering wheel or the accelerator, at the same time with a higher proportion of self-participation by the driver.
Preferably, the drifting assistance system can be activated by way of a kick down of the accelerator pedal.
According to an advantageous development, important driving data such as speed, yaw rate, side slip angle, etc. are recorded so as to enable the maneuvers made to be evaluated and analyzed together with a driving instructor.
Advantageously, the drifting training assistance system can also be obtained as special equipment for production vehicles.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings.